SIP Trunking

SIP Trunking allows businesses with legacy phone systems to benefit from the features and cost savings of IP telephony. By simply connecting existing infrastructure such as a PBX or phone system to the public telephone network with a SIP Trunk, businesses can use a single network for both data and voice saving £1000s each year on ISDN lines and call costs.



Integrate with your PBX

No upgrade or maintenance charges, only pay for a monthly licence fee.


Network convergence

Run voice and data across single IP Network without any loss in performance.


Save 70% compared to ISDN line rental

SIP Trunks typically cost 70% less than an equivalent ISDN30 line.


Quickly add call capacity

Increase call capacity without effecting existing infrastructure.


Reduced call charges

Our call charges are up to 30% cheaper when compared with BT.


Free calls between offices

Using SIP Trunks you can remove the cost of calls between offices.

Reduced ISDN line rental charges

With a SIP Trunk typically costing over 70% less than an ISDN30, customers could enjoy annual savings of over £4,770 per ISDN30 line if all 30 channels are in use. Quality of Service is guaranteed, with no degradation in performance.

Reduced call charges

Our call charges to UK local and national numbers are up to 30% cheaper when compared with BT. There are also no charges for internal calls between offices provided they are also connected via a SIP Trunk or Redcentric's hosted IP telephony service.

Why integrate a SIP Trunk with your existing telephony estate

Your business could be looking to expand into new sites, wanting to connect existing telephony systems or make use of your legacy telephony systems whilst benefiting from the features of IP telephony. SIP Trunks allow you to get the most out of your existing investments by facilitating an IP-enabled traditional PBX to deliver a full range of IP telephony features.

These features can provide improved business continuity, for example, using a SIP Trunk, incoming calls can be quickly redirected to another location, or a number of locations, from a web-based portal. You can also provide staff with the ability to redirect their personal phone number to any handset, such as a home number, so that they can continue to work even if there has been a major incident.

Also, SIP Trunks don't have to replace all ISDN lines, they can be installed simply to meet extra demand or for testing purposes; their inherent flexibility allows effortless scaling-up of capacity without affecting existing infrastructure.

SIP Trunking - Paving the way for Unified Communications

A SIP Trunk should be considered as a vital step for organisations wishing to include on-site phone systems as part of their Unified Communications strategy. Unlike ISDN, SIP Trunking provides a pathway to integration with other communications platforms, you could enjoy greater flexibility and scalability through full integration with hosted VoIP, a stepping stone to enable your organisation to benefit from productivity enhancing, cost-effective and green Unified Communications.

  • Single IP network - Run both voice and data over a single IP network without any loss in performance
  • Reduce or eliminate ISDN line rental charges
  • Free calls between offices - remove the cost of calls between your offices
  • Business continuity - in the event of a disaster calls can be redirected to other locations using our web portal
  • scalable on-demand - users can be added and removed without additional infrastructure or hardware
  • Integrates with other communications platforms as part of your Unified Communications strategy
  • Call centre functionality, call routing and voicemail
  • Free DDI rental
  • Online portal for management configuration
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